Much manual effort is expended in collecting litter and other debris from large community areas such as along streets and highways, parks, playgrounds, beaches and open commercial areas. Because of the difficulty of designing a machine which will collect the various types and sizes of litter and operate over various types of surfaces, manual retrieval is the usual method for collection. However, manual retrieval methods are slow, expensive and many times are ineffective, particularly where large areas must be patrolled.
Machines have been designed to supplement or replace the need manually pick up of litter. An effective apparatus for litter retrieval is disclosed in U.S. patent application No. 3,807,154 to Joseph L. Moore, issued Apr. 30, 1974 and assigned to the assignee of this application. This patent discloses the use of a towed apparatus having a rotatable drum which is rotated when in ground engagement. Flexible fingers extend radially from the drum and have a particular knob headed configuration for receiving bottles and cans which wedge between the fingers as the drum rolls over the ground. Bottles, cans and similar objects engaged by the drum and fingers are collected in a hopper after being stripped from between the fingers.
Although the device described in U.S. Pat. No. 3,807,154 is capable of retrieving some objects, such as bottles and cans, the effectiveness of the device has been less than completely satisfactory for other types of litter. Where the particular object cannot be grabbed between the resilient fingers extending from the drum, the apparatus may then fail to collect the debris.
An effective litter retrieving apparatus is also disclosed in U.S. patent Ser. No. 4,434,011 issued Feb. 28, 1984 to Joseph L. Moore and also assigned to the assignee of this application. This device includes a rotatable ground engaging drum acting with cooperating discs for collecting litter from the ground and directing such litter into a collector or a hopper. Another effective litter retrieving apparatus is also disclosed in the attached U.S. application Ser. No. 531,304 filed Sept. 9, 1983 by Joseph L. Moore and also assigned to the assignee of this application, such application being incorporated herein by reference. This apparatus includes a rotatable ground engaging drum in combination with a stripper mechanism including spring fingers which extend and retract relative to a carrier mechanism and which strips litter from between the fingers and directs litter to a conveyor.
The present application is directed to a litter retriever of the general form described in the prior Moore patents and application and in which the fingers are connected to the drum so they are easily removable and replaceable, reducing the costs of maintenence. The litter is stripped from between the fingers by a spring finger mechanism and deposited on a conveyor. The conveyor carries the material rearwardly and upwardly and into a collection hopper which, when full, is operated by an arrangement of linkage arms an pivots to raise upwardly, then swing rearwardly and tip to dump the litter.